Mattress spring with adjustable firmness

ABSTRACT

AN ADJUSTABLE COIL SPRING HAVING A TOP AND BOTTOM PLATE, A PLUNGER DEPENDING FROM THE TOP PLATE EXTENDS INTO A HOLLOW CYLINDER MOUNTED TO THE BOTTOM PLATE. THE CYLINDER INCLUDES A VERTICAL SLOT AND A PLURALITY OF RECESSES AN THE PLUNGER INCLUDES AN EXTENDING PIN WHICH IS ADAPTED TO RIDE ALONG THE SLOT AND ENGAGE ONE OF THE RECESSES FOR SELECTIVE CONTROL OF THE SPRING. ROTATION OF THE CYLINDER OR A PLURALITY OF CYLINDERS CONTROLS THE RECESS ADAPTED FOR ENGAGEMENT.

Sept. 28, 1971 B. KENTOR ETAL 3,608,107

MATTRESS SPRING WITH ADJUSTABLE FIRMNESS Filed Sept. 24, 1969 T3 Sheets-Shoot l mvsmons Boris Kentor 8 Theodore E. Anthony5R- Sept. 28, 1971 B. KENTOR ETAL 3,608,107

MATTRESS SPRING WITH ADJUSTABLE FIRMNESS Filed SepcJ 24, 1969 2 Sheets-Sheet 2 Fig.3.

mvzmons Boris Kontor 8:

Theodore E. Amhonym Patented Sept. 28, 1971 3,608,107 MATTRESS SPRING WITH ADJUSTABLE FIRMNESS Boris Kentor, 6536 Darlington Road 15217, and Theodore E. Anthony, Sr., 208 Rebecca Square 15209,

both of Pittsburgh, Pa.

Filed Sept. 24, 1969, Ser. No. 860,644 Int. Cl. A47c 23/04, 25/00 US. Cl. -351 8 Claims ABSTRACT OF THE DISCLOSURE An adjustable coil spring having a top and bottom plate. A plunger depending from the top plate extends into a hollow cylinder mounted to the bottom plate. The cylinder includes a vertical slot and a plurality of recesses and the plunger includes an extending pin which is adapted to ride along the slot and engage one of the recesses for selective control of the spring. Rotation of the cylinder or a plurality of cylinders controls the recess adapted for engagement.

This invention relates to springs for mattresses and the like and more particularly to such springs having means for varying their firmness or tension. The invention has particular value in the field of innerspring mattresses and provides generally an innerspring mattress of variable firmness.

It is common knowledge that there is no such thing as a mattress that everyone will find equally comfortable. Some like firm mattresses, others like soft ones. Some others require orthopedic-type mattresses which may be required to provide different degrees of firmness along their length.

It is known in the art to provide bed springs and the like of adjustable resiliency which enables the construction of a mattress or the like having adjustable firmness. For example, it has been proposed to provide a mattress of adjustable firmness wherein an innerspring is constructed comprising a relatively soft conventional coil spring which has mounted therein an additional auxiliary spring which may be independently expanded or compressed to thereby increase or decrease overall firmness 0f the combination of coil and auxiliary springs.

A variable firmness mattress spring has also been proposed wherein primary and secondary springs were located one upon the other. Tension of the primary spring relative to the other was adjusted by compressing or expanding a selected spring of the spring-pair by means of threaded connecting rods. These prior art devices have been undesirable and impractical for the reason that they are expensive, complicated and generally undesirable to manufacture and install in an innerspring system.

Moreover, no effective innerspring mattress system of adjustable firmness is known which can be conveniently and effectively constructed in conventional coil-springbased innerspring mattresses.

We provide a coil spring having adjustable firmness which overcomes the deficiencies of the prior art adjustable firmness coil spring systems, The spring of our invention may be adjusted to any desired firmness, and can be readily incorporated into conventional coil spring mattresses. We provide a mattress having variable firmness along its entire length thereby allowing for adjustment of mattress firmness for all different parts of the users body. In a preferred embodiment of our invention we provide a coil spring mattress "system comprising adjacent pairs of independently adjustable rows of coil springs wherein the firmness of either side of the mattress may be adjusted independently of the remaining side.

Though, as indicated above, the spring of adjustable firmness according to our invention is especially useful in connection with the manufacture of a variable firmness mattress, it is to be appreciated that the variable firmness Spring of our invention may be employed in any area of utility for a coil spring where adjustable firmness is desired. Such other areas of course include automobile seats, railroad and airline seats, etc.

Other details and advantages of our invention will become apparent from the following more detailed description thereof wherein:

FIG. 1 is a perspective of a covered innerspring mattress into which an innerspring system of variable firmness according to the invention may be incorporated;

FIG. 2 is a perspective of a typical spring in an innerspring system being of variable firmness according to the invention;

FIG. 3 is a side elevation view of an innerspring system having variable firmness according to the invention;

FIG. 4 is a plan view taken along line IV--IV of FIG. 3;

FIG. 5 is a detail of adjacent springs in an innerspring system having means for preventing lateral twisting or turning of those springs.

FIG. 2 shows a conventional coil spring 10 to which is attached upper and lower spring clamp plates 11 and 12, respectively. Clamp plates 11 and 12 are fixedly attached to coil spring 10, for example, as by having their ends pinched over the outermost coils of spring 10 as is shown in FIG. 2. Coil spring 10 is provided with firmness adjusting means according to the invention comprising generally a plunger 13 fixedly attached to upper spring clamp plate 11 which plunger is adapted to pass into and be received by cylinder 14. Cylinder 14 is rotably mounted upon lower spring clamp plate 12. A preferred means of rotably mounting said cylinder comprises stub shaft 15 rigidly attached to lower spring clamp 12 and extending upwardly into cylinder 14. The outside diameter of stub shaft 15 is preferably just slightly less than the inside diameter of cylinder 14 whereby cylinder 14 may rotate relative to stub shaft 15 while at the same time being maintained in a stable upright position.

Cylinder 14 has provided in its wall a vertical slot 17 beginning at the cylinders upper end and continuing downwardly to a remote point along the cylinder wall. Slot 17 is adapted to receive a pin 16 rigidly attached to plunger 13 and extending outwardly therefrom. Cylinder 14 is further provided with a series of stops 20, 21 and 22 which as shown are formed by a series of recesses cut into the wall of cylinder 14 along slot 17. The deepest stop 22 is formed by the termination of slot 17 itself.

Pin 16 on plunger 13 is adapted to pass into slot 17 and engage one of said several stops 20, 21 or 22. As is evident from the drawing the degree of compression of spring 10 depends directly upon the depth of penetration of plunger 13 into cylinder 14 and which in turn depends upon the point at which pin 16 on plunger 13 engages a particular stop. It can be seen that as plunger 13 is allowed to pass deeper into cylinder 14 the length of travel of the plunger increases, thereby decreasing the firmness of spring 10. Conversely as the penetration of plunger 13 into cylinder 14 is restricted spring 10 becomes more firm. Thus, it can be seen that by directing pin 16 to a particular stop, the firmness of spring 10 is adjusted.

As depicted in FIG. 2 plunger 16 is fixedly attached to upper spring clamp plate 11 on spring 10 and is therefore not rotatable. In order to direct pin 16 to the desired stop cylinder 14 is rotated about stub shaft 15 thereby placing the shoulder of a selected stop directly in line with the course of travel followed by pin 16 as plunger 13 penetrates cylinder 14. A suitable preferable means for rotating cylinder 14 is shown in FIG. 2 comprising an appendage 23 rigidly affixed to cylinder 14, e.g. as by welding or a threaded fitting. In the embodiment of the invention illustrated in FIG. 2 appendage 23 comprises an elongated rod having an upwardly extending elbow 23a operably attached to rod 24. Rod 24 extends to a point away from spring 10 such that cylinder 14 through appendage 23 and rod 24 may be rotated (and hence the firmness of coil spring adjusted) from a point remote from spring 10.

When springs of variable firmness according toour invention are located in a line, as they almost always are, e.g. in mattress springs, automobile seat springs, and cushions of all types (as shown in FIGS. 3 and 4) that rod may be a connecting rod operably attached to a series of cylinders 14 located along the line, for example, as through appendages 23. Thereby every cylinder located along that line is rotated exactly the same amount by a single adjustment of connecting rod 24.

Other stable means of connecting appendages 23 to rotate a series of cylinders located along a line may of course be used in place of connecting rod 24. For example, a single cable may be wound around each of the appendages. The cable may be spring loaded at one end of the row of springs whereby pulling the cable will adjust the spring firmness in one manner, and releasing the cable will adjust it in another (i.e. firm or soft).

When our springs of variable firmness are to be used in a mattress spring as for the case illustrated in FIGS. 3 and 4, it is desirable of course that the means for adjusting the mattress be out of sight so as to give the mattress a normal appearance. One such means is shown in FIG. 4 and comprises a semi-flexible leaf spring 25 attached to connecting rod 24 and rod 26 through screws 27. Rod 26 is connected to an indexing means which includes cylinder 28 having cut therein a longitudinal slot 30. Slot 30 is provided with detents 31. Rod 26 is adapted to pass into cylinder 30 and is provided with handle 29. Handle 29 is adapted to fit into and be retained by detents 31 as shown in the figures. Movement of handle 29 out of detent 31 causes rotation of rod 26 which may then be advanced in cylinder 28, and thereby move connecting rod 24 and hence adjust firmness of springs 10. Rotation of rod 26 causes a twisting of semi-flexible leaf spring 25 which continually urges handle 29 to return to a detent 31. Hence when not in operation handle 29 is always urged into and against a dentent 31 and spring firmness is maintained at a given selected level.

It is desirable in a mattress that lateral twisting or turning between adjacent springs be avoided. As shown in FIG. 4 lower spring clamp plates 12 are modified whereby adjacent springs in a line may be, through modified spring clamp plates 12, discouraged or prevented from lateral twisting or turning. The modification comprises bifurcating clamp plates 12 at one end thereof to provide a pair of tabs 12a which are adapted to receive there between a single tab 12b. Both tabs 12a and 12b are foldable over adjacent springs 10 and in that manner relative lateral movement between them is prevented.

In FIG. another means of preventing lateral twisting or turning of adjacent springs is shown. There spring is provided with notch 9 adapted to receive a similar notch on an adjacent spring 10.

In FIG. 1 a covered innerspring mattress 1 is shown having access means such as zippers 2 along the sides thereof. Opening of zippers 2 exposes the means for adjusting the variable firmness springs of the invention. In a preferred embodiment of our invention a larger size mattress (double, queen, king, etc.) is provided having the adjustable firmness springs of our invention arranged in independently adjustable rows on either side of the center line of the mattress. In that case, zippers 2 are provided on both sides of the mattress whereby the firmness of any portion of the mattress on either side thereof may be independently adjusted.

The spring having adjustable firmness of our invention is readily assimilated into conventional coil springs and into arrays of such springs as found in mattresses and the like. It is believed that our invention offers the first practical solution to providing an innerspring mattress of variable and adjustable firmness.

The foregoing has illustrated the spring having adjustable firmness of our invention and certain preferred embodiments thereof. It is to be appreciated, of course, that our invention may be variously practiced within the scope of the appended claims.

What is claimed is:

1. A spring having adjustable firmness comprising:

(a) a coil spring having fixedly attached thereto on its outermost coils top and bottom end plates respectively;

(b) a plunger extending downwardly from said top end plate and rigidly aflixed thereto;

(c) a hollow cylinder extending upwardly from said bottom end plate and rotatably mounted thereon;

(d) a vertical slot in said cylinder wall beginning at its upper end and containing downwardly therefrom;

(e) a pin on said plunger and extending outwardly therefrom;

(f) a plurality of recesses in said cylinder wall along said slot;

said plunger being adapted to pass into and be received by said cylinder whereby said pin passes into said slot to engage a selected recess of said plurality of recesses along said slot.

2. The spring of claim 1 including a stub shaft on said bottom end plate and extending upwardly into said hollow cylinder, and an appendage fixed to and extending outwardly from said cylinder whereby movement of said appendage rotates said cylinder about said stub shaft.

3. A row of springs having adjustable firmness, each of said springs comprising a coil spring having to and bottom end plates, a plunger extending downwardly from said top end plate, a hollow cylinder extending upwardly from said bottom end plate, a vertical slot in said cylinder wall beginning at its upper end and continuing downwardly therefrom, a plurality of recesses in said cylinder wall along said slot, a pin on said plunger and extending outwardly therefrom, means for simultaneously rotating each of said cylinders, each of said plungers being adapted to pass into and be received by a corresponding cylinder whereby said pins pass into said slots to engage a selected recess of said plurality of recesses in said cylinder.

4. The row of springs of claim 3 wherein said means for simultaneously rotating said cylinders comprises an appendage extending from each of said cylinders and a connecting rod operably attached to said appendages whereby movement of said connecting rod rotates said cylinders simultaneously.

5. The row of springs of claim 3 wherein said means for simultaneously rotating said cylinder comprises an appendage extending from each of said cylinders and cable means operably attached to said appendages whereby movement of said cable rotates said cylinders simultaneously.

6. The row of springs of claim 5 whereby said cable means is spring-loaded at one end thereof whereby pulling said cable means will rotate said cylinder in one direction and releasing said cable will rotate said cylinder in the opposite direction.

7. An innerspring mattress of adjustable firmness having an innerspring system comprising rows of springs having adjustable firmness, each of said springs comprising a coil spring having top and bottom end plates, a plunger extending downwardly from said top end plate, a hollow cylinder extending upwardly from said bottom end plate, a vertical slot in said cylinder wall beginning at its upper end and continuing downwardly therefrom, a plurality of recesses in said cylinder wall along said slot, a pin on said plunger and extending outwardly therefrom, means 6 for simultaneously rotating each of said cylinders, each References Cited of said plungers being adapted to pass into and be received UNITED STATES PATENTS by a corresponding cylinder whereby said PlIlS pass into said slots to engage a selected recess of said plurality of 2,595,072 4/1952 Gottschalk 5248 recesses in aid cylinder Grund 5 3,058,778 10/1962 Campbell 297-452 8. An innerspring mattress of adjustable firmness, having an innerspring system comprising adjacent pairs of independently adjustable rows of coil springs according CASMIR NUNBERG Pnmary Exammer to claim 3 whereby the firmness of either side of said US Cl XR mattress may be adjusted independently of the remaining 10 267 89 side at any point along its length. 

